samsung: doze: Protect com.android.systemui.doze.pulse

As stated in ActivityManagerService:

  The vast majority of broadcasts sent from system internals
  should be protected to avoid security holes

Change-Id: I1dc989d9d132d40835ca8dbf277285eb88e30a58

doze/AndroidManifest.xml

@@ -10,6 +10,8 @@
     <uses-permission android:name="android.permission.VIBRATE"/>
     <uses-permission android:name="android.permission.WAKE_LOCK" />
 
+    <protected-broadcast android:name="com.android.systemui.doze.pulse" />
+
     <uses-sdk
         android:minSdkVersion="21"
         android:targetSdkVersion="21"/>